complile_run

:: compile and rename to hello
g++ hello.cpp -o hello
g++ -Wall -std=c++14 hello.cpp -o hello


:: execute the compiled code
./hello

stringInString.cpp

#include <iostream>
#include <string>
using namespace std;

// found=str.find("haystack");
// if (found != string::npos)
//     std::cout << "'haystack' also found at: " << found << '\n';

int main() {
   string userLine;
   string t1 = "I don't know";
   string t2 = "talk to you later";
   string t3 = "just kidding";
   string t4 = "best friend forever";
   string t5 = "too much information";
   size_t pos;
   cout << "Enter text:\n";
   getline(cin, userLine);
   cout << "You entered: " << userLine << "\n";
   
   while((pos = userLine.find("IDK")) != string::npos){
      userLine.replace(pos, 3, t1);
   }
   
   if((pos = userLine.find("BFF")) != string::npos){
      userLine.replace(pos, 3, t4);
   }
   
   while((pos = userLine.find("JK")) != string::npos){
      userLine.replace(pos, 2, t3);
   }

   while((pos = userLine.find("TMI")) != string::npos){
      userLine.replace(pos, 3, t5);
   }

   while((pos = userLine.find("TTYL")) != string::npos){
      userLine.replace(pos, 4, t2);
   }
   
   cout << "Expanded: "<< userLine << "\n";


   return 0;
}

variableDecloration.cpp

#include <iostream>

using namespace std;

int main()
{

  int dog_age = 3;
  
  int early_years, later_years, human_years;

  early_years = 21;

  later_years = (dog_age - 2) * 4;

  human_years = early_years + later_years;

  cout << "My name is Sparkles! Ruff Ruff, I am " << human_years << " years old in human years.\n";

}